On the weekend, I typically grant myself the luxury of waiting until sunrise to run. The winter’s long nights and sparse sunlight weighs on me and the weekday predawn runs add to the emotional load. I find that running after dawn, even on a cold, overcast, Maryland winter’s day is a relief from the darkness.

Today was a bit different. I spent the first hour padding around the house, first taking the chihuahua out, then making coffee for Denise and me. I took the time to grind her coffee beans to make that first cup of coffee specially good. I turned up the heat to 74 F and had humidifiers running in both the basement and the second floor. Denise got up and settled into her chaise with Peanut in her lap. I fell to updating various exercise note that I often do not have time to do during the work week. We were very comfortable in our shell, isolated from the predawn 27 F darkness.

Comfort. It appeals. Evolution scientists tell us that we probably have an instinct to be comfortable. It conserves life-ensuring energy. It saves calories for lean times. Studies show that the more people exercise, the more likely they are to be less active the rest of the day. This often stymies exercisers who are trying to lose weight. The 300 calorie run or 150 calorie weight work out is easily offset the rest of the day by being less active and, perhaps, indulging in a food reward.

I sat typing on my laptop in the warmth. My mind wandered. Comfort. Comfort means lack of movement. Lack of movement means slow atrophy of everything that keeps us healthy and alive. Muscles weaken and lose their innervation. Tendons and ligaments weaken. Motor function declines. Mitochondria shrink and disappear. Metabolic pathways that produce energy become sparse. Chromosome-protecting telomeres shorten, increasing the rate of the aging process. Lean mass declines; adipose mass increases. Quality of life declines. Morbidity increases. All the symptoms we mistakenly associate with aging increase their presence. George Sheehan put it succinctly: “You don’t stop running when you get old, you get old when you stop running.”

Hunter-gatherers do not have the luxury of being comfortable all the time. Hunger will inevitably intrude on indolent repose. Its bite is far worse than any desire to stay at rest, inspiring movement and the search for food. This search or hunt can become pleasurable in itself. Fit humans engaging in prolonged activity are often rewarded when their bodies release endorphins that decrease any pain and increases the sense of positive well-being. This enables the hunter or gatherer to continue effort for longer than he/she would feel inclined. We have evolved to enjoy the feeling of effort, as well as the feeling of no effort.

I dragged myself out of my repose, along with Denise. We went for 3 miles just before the crack dawn. It wasn’t comfortable. I ran another 3.1, after after leaving her at home. It was dawn and I worked harder. The sunrise always raises my spirits. Greater effort, pounding heart, lungs sucking air…it felt better. Elevated post-exercise oxygen consumption (EPOC), or after-burn, is greatest after more intense exercise. Likewise, so is the morphine-like endorphin high.

Now, as I type this, I’m comfortable again. I’m more comfortable than I was while I was sipping my first cup of coffee as I am at mental peace. My mind knows that my body is now repairing itself. My experience of satisfied mind and strengthening body are optimized by being comfortable.

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